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arXiv · 1405.2945

Generating the Ideals Defining Unions of Schubert Varieties

Anna Bertiger
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Abstract

This note computes a Gr\"obner basis for the ideal defining a union of Schubert varieties. More precisely, it computes a Gr\"obner basis for unions of schemes given by northwest rank conditions on the space of all matrices of a fixed size. Schemes given by northwest rank conditions include classical determinantal varieties and matrix Schubert varieties--closures of Schubert varieties lifted from the flag manifold to the space of matrices.

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Anna Bertiger. 2014-05-12. Generating the Ideals Defining Unions of Schubert Varieties. https://arxiv.org/abs/1405.2945

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